If I'm working on a physical painting, I need a paper towel to blot, smear, lift, and otherwise abuse paint. Generally, living in the perpetual snuffly twilight of the allergic, I also require a Kleenex.
You can probably see where this is going.
Not unlike dipping one's paintbrush into one's coffee, it's inevitable that sooner or later worlds collide. A fast-running drip--of either variety--will require immediate attention, and I will grope for whatever is at hand. Kleenex as blotter is rarely too bad--if the Kleenex has reached the heavily used state, I've thrown it out already, so I am rarely in danger of accidentally spreading the contents of my sinuses across a canvas, and it just means I go through Kleenex a bit faster.
If, on the other hand, I have just thrown out my Kleenex, or knocked it on the floor as I flailed wildly across the little end table that serves as my essential-stuff-holder or the cat has made off with it--well, any port in a storm, and there's a big, heavy-duty Viva paper towel, guaranteed to soak up anything RIGHT THERE, clutched in my off hand. And--well, I can't imagine anyone on earth has gotten away with not experiencing, at least once, that hideous sensation whereby the nasal cavaties sudden decide they've had enough, rebel, and send the occupants packing south of the border, and suddenly you have about one second to find SOMETHING or else...it ain't gonna be pretty. This is a cultural taboo up there with bedwetting--you get that immediate, visceral oh-shit-bodily-fluids-escaping! Noo! panic, and living as we do in a decorous society, the paper-to-nose reflex is so strongly ingrained that it would take a stronger soul than me to fight it.
Even a paper towel that has been catching paint for a coupla minutes now.
Which is, of course, how my nose and cheekbone got slathered in Quinacradone Violet and a smidge of Naples Yellow.
Good thing acrylic is non-toxic...